<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>

    <style>
        * {
            list-style: none;
            margin: 0;
            padding: 0;
        }

        #shop-car li {
            border: 1px dotted red;
            margin: 20px 0;
            padding: 20px;
        }

        .container {
            width: 400px;
            padding: 20px;
        }
    </style>

    <div class="container">
        <ul id="shop-car">
            <li>
                <input type="checkbox" />
                <div>商品名称:</div>
                <img src="https://img12.360buyimg.com/n0/s80x80_jfs/t1/118064/27/12885/59959/5f17b7efE453f688d/5b33ac76b2aaea9b.jpg"
                    alt="">
                <div>商品价格:50</div>
                <div>购买数量:30</div>
                <div>商品规格: 黑</div>
                <div>是否选中：选中吧OR不选中</div>
            </li>
        </ul>
        <p id="totalnum">
            <!-- 总数量：xxx -->
        </p>
    </div>


    <script src="./jquery.js"></script>
    <script>
        let products = [{
                goods_name: '小米10-1',
                goods_img: 'https://img12.360buyimg.com/n0/s80x80_jfs/t1/118064/27/12885/59959/5f17b7efE453f688d/5b33ac76b2aaea9b.jpg',
                goods_price: '500',
                goods_attr: '砂石黑4GB+64GB',
                goods_num: 10,
                goods_is_checked: true
            },
            {
                goods_name: '小米10-2',
                goods_img: 'https://img12.360buyimg.com/n0/s80x80_jfs/t1/118064/27/12885/59959/5f17b7efE453f688d/5b33ac76b2aaea9b.jpg',
                goods_price: '510',
                goods_attr: '砂石黑4GB+64GB',
                goods_num: 50,
                goods_is_checked: false
            }
        ]

        let ul_str = ''
        let p_str = ''
        let sum = 0
        for (let i = 0; i < products.length; i++) {
            ul_str +=
                `<li>
                <input type="checkbox" ${products[i].goods_is_checked?'checked':''}>
                <div>商品名称:${products[i].goods_name}</div>
                <img src=${products[i].goods_img} alt="">
                <div>商品价格:${products[i]. goods_price}</div>
                <div>购买数量:${products[i].goods_num}</div>
                <div>商品规格: ${products[i].goods_attr}</div>
                <div>是否选中：${products[i].goods_is_checked?'选中':'不选中'}</div>
            </li>`
            $('#shop-car').html(ul_str)
            products[i].goods_is_checked ? sum +=products[i].goods_num:''
        }

        // let re = products.filter(function (v) {
        //     return v.goods_is_checked
        // })

        // console.log(re);

        // for (let i = 0; i < re.length; i++) {
        //     sum += re[i].goods_num
        // }
        $('p').html(`总数量：${sum}`)


        $(':checkbox').click(function () {
            let num1 = 0
            if ($(this).prop('checked')) {
                $(this).siblings('div').eq(4).html('是否选中：选中')
                num1 = $(this).siblings('div').eq(2).text().substring(5)
            } else {
                $(this).siblings('div').eq(4).html('是否选中：不选中')
                num1 = -$(this).siblings('div').eq(2).text().substring(5)
            }
            sum = sum + +num1
            $('p').html(`总数量：${sum}`)
        })
    </script>
</body>

</html>